Field of the Invention
The present invention relates to an apparatus and method for manufacturing an interior part of a vehicle. More particularly, it relates to an apparatus and method for manufacturing an interior part of a vehicle, such as a crash pad, which is configured to prevent sealing portions of skin and foamed layers of the crash pad from being separated from a base due to reduction in adhesiveness.
Description of Related Art
Among parts representative of an interior part of a vehicle, a crash pad, which is disposed in front of a driver's seat and a front passenger's seat and defines the boundary with respect to a windshield glass, may be proposed.
Such crash pads have different designs in accordance with the types of vehicles, and are installed at the area in front of a driver's seat and a front passenger's seat, excluding a center fascia panel and the like, on which a cluster, a head unit, an air conditioner and the like are mounted.
The crash pad is made of a material serving to define the functional appearance of a vehicle and capable of absorbing impact. The crash pad is made of Polyvinyl chloride (PVC), Thermoplastic Poly Urethane (TPU) or the like, which are representative thermoplastic materials.
The conventional process of manufacturing a crash pad, which is an interior part of a vehicle, will be described as follows.
FIGS. 1 and 2 of the accompanying drawings are schematic cross-sectional views illustrating a conventional crash pad and a conventional method of manufacturing the same.
As shown in FIGS. 1 and 2, the crash pad 110 includes a base 112 constituting a framework of the crash pad 110, a foamed layer 14 formed on the base 112, and a skin layer 116 defining the appearance of the crash pad to protect the foamed layer 114.
The foamed layer 114 is made of a polyurethane material, and the skin layer 116 is made of a PVC material and shaped in accordance with the design of the vehicle.
In order to manufacture the conventional crash pad 110, the base 112 constituting the framework of the crash pad and the skin layer 16 defining the appearance of the crash pad are first prepared in a predetermined shaping manner in accordance with the design of the vehicle.
Preferably, the skin layer 116 is made of a PVC material including a predetermined amount of plasticizer so as to impart a soft feeling and shock resistance to the crash pad.
Subsequently, a polyurethane foam material is disposed on the base 112, and then the skin layer 116 is disposed on the polyurethane foam material.
A sealing foam tape 118 adheres to the mating marginal surfaces of the base 112 and the skin layer 116, that is, the upper marginal surface of the base 112 and the lower marginal surface of the skin layer 16, in order to prevent the leakage of the foam material after foaming.
Accordingly, a hermetic space is defined between the base 112 and the skin layer 116 by virtue of the sealing foam tape 118, and the foam material is disposed in the hermetic space.
Subsequently, on a predetermined form condition, the foam material present between the base 112 and the skin layer 116 is foamed, and thus the hermetic space between the base 112 and the skin layer 116 is completely filled with the foamed layer 114.
However, the conventional process of manufacturing a crash pad has the following problems.
As shown in FIG. 1, since the foaming pressure of the foam material disposed between the base and the skin layer is higher than the adhesive force of the sealing foam tape, which sticks the base and the skin layer at the time of foaming of the foam material, the foam material may leak to the outside through the sealing foam tape, which results in a defective foamed layer, thereby significantly lowering the quality of the resulting crash pad.
When the foam material disposed between the base and the skin layer is foamed, air in the foaming space cannot escape therefrom due to the sealing foam tape, and the resulting foamed layer may include air bubbles therein, thereby lowering the foaming quality and durability of the foamed layer.
As shown in FIG. 2, the skin layer of the crash pad includes a predetermined amount of plasticizer in order to impart a soft feeling and shock resistance to the crash pad. When the crash pad has aged after the lapse of a certain period of time, the plasticizer migrates into the sealing foam tape, thereby significantly reducing the adhesive force of the sealing foam tape. As a result, the sealing foam tape having the reduced adhesive force and the adjacent skin layer and foamed layer are lifted and separated from the base, thereby significantly reducing the durability of the crash pad.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.